/Engine/Source/Editor/UnrealEd/Public/ClassIconFinder.h
Find the large thumbnail name to use for the supplied class
static const [FSlateBrush](API\Runtime\SlateCore\Styling\FSlateBrush) * FindThumbnailForClass ( const [UClass](API\Runtime\CoreUObject\UObject\UClass) * InClass, const [FName](API\Runtime\Core\UObject\FName) & InDefaultName )